278 research outputs found

    Possible Charge-Exchange X-Ray Emission in the Cygnus Loop Detected with Suzaku

    Get PDF
    X-ray spectroscopic measurements of the Cygnus Loop supernova remnant indicate that metal abundances throughout most of the remnant's rim are depleted to about 0.2 times the solar value. However, recent X-ray studies have revealed in some narrow regions along the outermost rim anomalously "enhanced" abundances (up to about 1 solar). The reason for these anomalous abundances is not understood. Here, we examine X-ray spectra in annular sectors covering nearly the entire rim of the Cygnus Loop using Suzaku (21 pointings) and XMM-Newton (1 pointing). We find that spectra in the "enhanced" abundance regions commonly show a strong emission feature at about 0.7 keV. This feature is likely a complex of He-like O K(gamma + delta + epsilon), although other possibilities cannot be fully excluded. The intensity of this emission relative to He-like O Kalpha appears to be too high to be explained as thermal emission. This fact, as well as the spatial concentration of the anomalous abundances in the outermost rim, leads us to propose an origin from charge-exchange processes between neutrals and H-like O. We show that the presence of charge-exchange emission could lead to the inference of apparently "enhanced" metal abundances using pure thermal emission models. Accounting for charge-exchange emission, the actual abundances could be uniformly low throughout the rim. The overall abundance depletion remains an open question.Comment: Published in Ap

    The relationship between psychological comfort space and self-esteem in people with mental disorders

    Get PDF
    The purpose of this study was to demonstrate a causal model of the sense of having psychological comfortable space that is call ‘ibasho’ in Japanese and self-esteem in people with mental disorders who had difficulty in social activities. The subjects were 248 schizophrenia patients who were living in the community and receiving day care treatment. Data were collected from December 2007 to April 2009 using the Scale for the Sense of ibasho for persons with mentally ill (SSI) and the Rosenberg Self-Esteem Scale (RSES), and analyzed for cross-validation of construct validity by conducting covariance structure analysis. A relationship between the sense of having comfortable space and self-esteem was investigated. Multiple indicator models of the sense of having psychological comfortable space and self-esteem were evaluated using structural equation modeling. Furthermore, the SSI scores were compared between the high- and low-self-esteem groups. The path coefficient from the sense of having comfortable space to self-esteem was significant (0.80). High-self-esteem group scored significantly higher in the SSI subscales, ‘the sense of recognizing my true self’ and ‘the sense of recognizing deep personto- person relationships’ than the low-self-esteem group. It was suggested that in order to help people with mental disorders improve self-esteem, it might be useful to support them in a way they can enhance the sense of having comfortable space

    Development of the Anger Coping Behaviors Style Scale for High School Students

    Get PDF
    The reliability and validity of the Anger Coping Behaviors Style Scale for High School Students were examined in this study. In the analysis, we used the data of senior high school students in A Prefecture (n=3360) who had no missing values on the survey items. We extracted the following four factors using exploratory factor analysis: Support seeking, Situation analysis, Escape, and Violence. Then, we examined the factorial validity of the scale using confirmatory factor analysis, which indicated that an oblique factor model consisting of these four factors fitted the data(CFI: Comparative Fit Index=0.955, RMSEA: Root Mean Square Error of Approximation=0.070). The results of statistical analysis supported the reliability and validity of the Anger Coping Behaviors Style Scale for High School Students developed in this study

    リン脂質過酸化物の生物有機化学的合成

    Get PDF
    Chemoenzymatic synthesis of 1-stearoyl-2-hydropeoxyacyl-sn-glycerophospholipids including phosphatidylcholine (PC-OOH), phosphatidic acid (PA-OOH), phosphatidylethanolamine (PE-OOH), phosphatidylglycerol (PG-OOH) and phosphatidylserine (PS-OOH). The hydroperoxy acyl moieties were prepared via hydroperoxidation of linoleic, dihomo-γ-linolenic and arachidonic acids by soybean, potate lipoxygenase or autoxidation. Their hydroperoxy group was protected as a dimethylperacetal before condensation with lysophosphatidylcholine. Optically active lysophosphatidylcholine was prepared via short pathway involving lipase-catalyzed direct enantioselective stearoylation of 2-O-benzylglycerol and choline phosphate synthesis. Peroxy fatty acids and lysophosphatidylcholine thus obtained were condensed using dicyclohexylcarbodiimide in chloroform. Removing the peracetal group in the product and purification by reverse-phase chromatography afforded the desired PC-OOH’s. PA-OOH, PG-OOH, PE-OOH and PS-OOH were obtained by phospholipase-D catalyzed transphosphatidylation from PC-OOH. As a reference compound for biological studies of hydroperoxy phopholipid, PC-OH's were also prepared in which hydroxy unsaturated fatty acyl group was linked to the sn-2 position of the glycerophospholipids.健康正常人の血液などの組織中にはリン脂質過酸化物が極微量で存在し,疾病や老化によってその濃度が顕著に上昇する事が知られている.その事が明らかにされた当初は,極めて複雑な混合物をなす生体脂質中に含まれる不安定な極微量の過酸化脂質を単離・構造決定する事は殆ど不可能と考えられていた.現在もなお,そのような脂質過酸化物を生体組織から純粋に取り出し,構造決定したという報告は無い.従ってそのような分子種の化学的・生理学的性質は不明であったが,脂肪酸過酸化物が毒性を示す事から,リン脂質過酸化物もおそらく毒性を示すだろうと考えられてきた.このような漠然とした推定を科学的に明らかにするためには,化学合成によらざるを得ない.我々はこの未知の合成に取りかかった.しかし,従来の化学的手法のみでは不可能である事も明らかであった.その中で予想された困難の一つは極めて不安定なヒドロペルオキシ基を不飽和脂肪酸のある特定の位置にどのように導入するかという問題と,ヒドロペルオキシ基に影響を与える事なく合成中間体をどのように化学変換するかであった.第一の問題に対する解決策として,不飽和脂肪酸に大豆リポキシゲナーゼを作用させる事で解決する事ができた.植物に広く分布する酵素であるリポキシゲナーゼは植物中でリノール酸に作用して過酸化し,その生成物にヒドロペルオキシドリアーゼという酵素が作用して種々のアルデヒドが精製し,これは植物の青臭みを与える.第二の問題に対しては,リノール酸に導入された不安定なヒドロペルオキシ基をパーアセタールとしての保護する事により解決した.この保護基は,中間体から最終生成物に至るまでの反応条件,例えばDCCによるアシル化反応に対して安定である事が明らかとなった.この二つの問題を解決する事によって,リン脂質過酸化物の一つであるホスファチジルコリン過酸化物を世界に先駆けて成功した.さらにこのホスファチジルコリン過酸化物に微生物由来のホスフォリパーゼDを作用させる事によってホスファチジルエタノールアミン過酸化物,ホスファチジルセリン過酸化物やホスファチジルグリセロール過酸化物の合成にも成功した.また,トリグリセリド過酸化物の合成も可能になった.これらの脂質過酸化物が化学的に実態のあるものとして認識されてから,その生理作用に関する研究が広範に行われている.しかし,生体組織に存在するリン脂質過酸化物の生理学的役割は依然として明らかになっていない.ある種のリン脂質過酸化物が動物の免疫系を活性化するという報告もあり,必ずしも生体に対して悪い作用をするばかりではないようである
    corecore